Bill Venners: You said in your keynote, "Errors discovered with real data seem to me to be the hardest to find." Bruce Eckel: Yes. If I'm writing a Python program, I can very rapidly get to the point where I have a working program, and then I can actually feed it real data. And it seems like certain kinds of errors are much harder to find without putting real data into it. When you're trying to make something, the closer you can get it to the real thing as soon as possible, the more you'll find out about it early on. You really have to get it that close, or things will slip through the cracks. Bill Venners: You're saying it takes me longer to write code that is statically checked at compile time, but the problems the compiler finds are not the kind of problems that have to do with real data. Bruce Eckel: That's actually very well put. Once I get the program running, I feed it real data. Then I'm going to find some interesting errors. So the sooner I can do that, the sooner I can find those errors.